Best tools for tracking LLM costs in production (2026)

Engineering teams aiming to optimize and track LLM costs in production are increasingly focused on tools that provide detailed visibility into token spending associated with various workflow steps, including long prompts, retries, and tool calls. Among the tools evaluated, Braintrust stands out for its comprehensive approach, offering trace-level visibility that captures every LLM call, retrieval step, and tool invocation, allowing teams to attribute costs precisely and experiment with cheaper prompts or models. Braintrust's system integrates cost data with quality checks, ensuring that any cost-saving changes maintain output integrity before release. It enables prompt and model experimentation with real production traces and includes an AI assistant, Loop, that automatically proposes optimizations based on failure patterns. With its focus on seamless integration of cost tracking and quality assurance, Braintrust is particularly recommended for production teams requiring robust cost control measures, as evidenced by its adoption by companies like Stripe, Vercel, and Airtable.